Using Multiple X3D/VRML Clients
At some point, like it or not, you'll need to have multiple X3D clients on your machine to test content with or because you have multiple projects dedicated to different clients. Go here
and read the thread. There are two good free/cheap solutions to how to do this provided by other community members. This is good mojo from the X3DHeads. Send them a note and say Thank you for the juju.